1. Field of the Invention
The present invention relates to a capsule for a tooth restoring material, which is used when the tooth-restoring material consisting of liquids and powder, two components are used for filling, fitting, relining, filling-up or other tooth restoration.
2. Statement of the Prior Art
In general, tooth-restoring materials are filled for the restoration of tooth cavities. Such tooth-restoring materials are usually based on two components which react easily with each other by mixing. The two-component materials often comprise a combination of powders and liquids, which are now put on the market, while filled in glass or plastic bottles. Such two-component materials should be filled in cavities as rapidly as possible prior to curing, since their curing reaction proceeds immediately upon mixing.
The manipulations for weighing and mixing together the aforesaid bottled materials with a spatula just prior to filling are troublesome and time consuming. Hence, there have recently been commercially available capsules in which a certain amount of powders and liquids is contained in an isolated state. Such capsules dispense with any weighing manipulation, and mixing of the two components upon combined together is finished within several seconds by applying mechanical vibrations thereto.
Even with the capsules in which the pre-weighed amounts of tooth-restoring materials are contained, a considerable time is still required to fill them in cavities, since the thus mixed content should first be transferred to a separate vessel. In particular, the curing reaction of the mixed tooth-restoring materials proceeds more rapidly at elevated temperatures. Thus, not a few failures occur, because such curing reaction have already proceeded to a some extent at the time of filling.
We have made various studies to solve the problems as mentioned above and, as disclosed in Japanese Utility Model Application No. 60(1985)-201319, have proposed a syringe assembly of extruding the tooth-restoring material contained in a capsule. Immediately upon mixing of the tooth-restoring material contained in the capsule, that syringe assembly is attached to the capsule to allow rapid pouring thereof into a tooth cavity through a nozzle fitted to the tip of the capsule without either interferring with the visual examination of a narrow region to be restored in the mouth cavity or applying pressure to a patient.
The development of such a syringe assembly has enabled the tooth-restoring material mixed in the capsule to be rapidly filled in the region to be restored. However, there are still problems of wherein the tooth-restoring material consisting of powders and liquids and contained in the associated capsule in an isolated state, the package with the liquid components being filled therein in pre-located in the capsule, or how the liquid component of the package is mixed with the powder component and guided to the tooth region to be restored.
For instance, we take a capsule comprising a dental formulation-mixing container of such a structure as disclosed in Japanese Utility Model Publication No. 55(1980)-46625. A package containing therein the liquid component of the tooth-restoring material and breakable by giving pressure thereto (hereinafter called a breakable package) is positioned on the side of the cylinder. The overall configuration of the package is thus complicated from the need of providing an additional location for mounting a clip for holding the package on the side of the cylinder. The presence of such a clip leads to a further disadvantage that the diameter of the capsule is larger than required. Furthermore, a pin must be attached to the tip of the cylinder to prevent an outflow of the tooth-restoring material mixed, thus rendering the manipulation more troublesome.